package com.syni.mdd.yhd.common.all.utils;

import lombok.extern.log4j.Log4j2;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * @className NetFileUtil
 * @description TOO
 * @Author cfx
 * @DATE 2019/11/21 9:23
 * @VERSION 1.0
 **/
@Log4j2
public class NetFileUtil {
    /**
     * 从网络Url中下载文件
     * @param urlStr
     * @param fileName
     * @param savePath
     * @throws IOException
     */
    public static String  downLoadFromUrl(String urlStr,String fileName,String savePath){
        URL url = null;
        try {
            url = new URL(urlStr);
            HttpURLConnection conn = (HttpURLConnection)url.openConnection();
            //设置超时间为3秒
            conn.setConnectTimeout(3000);
            //防止屏蔽程序抓取而返回403错误
            conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)");

            //得到输入流
            InputStream inputStream = conn.getInputStream();
            //获取自己数组
            byte[] getData = readInputStream(inputStream);

            //文件保存位置
            File saveDir = new File(savePath);
            if(!saveDir.exists()){
                saveDir.mkdir();
            }
            File file = new File(saveDir + File.separator + fileName);
            FileOutputStream fos = new FileOutputStream(file);
            fos.write(getData);
            if(fos!=null){
                fos.close();
            }
            if(inputStream!=null){
                inputStream.close();
            }
            System.out.println("info:" + url +" download success");

        }catch (Exception e){
            log.error(e.getMessage(),e);
        }
        return savePath + "/" + fileName;
    }


    /**
     * 从输入流中获取字节数组
     * @param inputStream
     * @return
     * @throws IOException
     */
    public static  byte[] readInputStream(InputStream inputStream) throws IOException {
        byte[] buffer = new byte[1024];
        int len = 0;
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        while((len = inputStream.read(buffer)) != -1) {
            bos.write(buffer, 0, len);
        }
        bos.close();
        return bos.toByteArray();
    }
}
